The present invention relates to a sensor with built-in circuits having a sensor region and circuit region provided on a semiconductor substrate, and to a pressure detector using the same.
There is a known pressure sensor with built-in circuits having provided on the same semiconductor substrate a sensor region for converting pressure into an electric signal, and a circuit region that is formed of a signal detection circuit for detecting the electric signal and a signal processing circuit for processing the electric signal, as disclosed in, for example, “An Integrated Silicon Bulk Micromachined Barometric Pressure Sensor for Engine control Unit and External Mount” (Motorola Semiconductor Application note (1998)).
In this conventional example, a piezo-electric resistance type pressure transducer having a piezo-electric resistance formed on a silicon diaphragm that is formed by etching a semiconductor substrate, and other elements such as operational amplifiers, active elements and passive elements including resistors for correction and compensation are formed on the same semiconductor substrate by a bipolar integrated circuit technology. An external pressure is exerted from below on the sensor.